On some Sony Readers, you may receive a "Protected Page" error when trying to open eBooks.
This error occurs on some models of Sony Readers when transferring protected eBooks and alternating between PDF and EPUB formats.
To resolve this error, transfer a new book using the same format as the one giving you issues. After that, you should be able to open eBooks in the new format.
For example, if you transfer an EPUB eBook to your Sony Reader and later get the "Protected Page" error when attempting to open the book, you need to transfer another EPUB eBook to your device. This will clear the "Protected Page" error for all EPUB eBooks on your Sony Reader.
Sony has fixed this issue on the following Reader models:
If you have one of the above models and are still experiencing difficulty, please try updating the firmware on your device.